Throttling by product, but applied on operation-level

advanced-frament.policy.xml

<!--
    IMPORTANT:
    - Policy fragment are included as-is whenever they are referenced.
    - If using variables. Ensure they are setup before use.
    - Copy and paste your code here or simply start coding
-->
<fragment>
    <rate-limit-by-key calls="@(int.Parse((string)context.Variables["amountOfCalls"]))" renewal-period="@(int.Parse((string)context.Variables["renewalPeriod"]))" counter-key="@(context.Subscription.Id)" remaining-calls-variable-name="remainingCallsPerSubscription" />
</fragment>

advanced-operation-with-fragment.policy.xml

<policies>
    <inbound>
        <base />
        <include-fragment fragment-id="operation-level-rate-limiting" />
    </inbound>
    <backend>
        <base />
    </backend>
    <outbound>
        <base />
        <set-header name="X-RateLimit-Reset" exists-action="override">
            <value>@(((int)context.Variables["remainingCallsPerSubscription"]).ToString())</value>
        </set-header>
    </outbound>
    <on-error>
        <base />
    </on-error>
</policies>

product.policy.xml

<policies>
    <inbound>
        <set-variable name="amountOfCalls" value="10" />
        <set-variable name="renewalPeriod" value="60" />
        <base />
    </inbound>
    <backend>
        <base />
    </backend>
    <outbound>
        <base />
        <set-header name="X-RateLimit-Renewal" exists-action="override">
            <value>@((string)context.Variables["renewalPeriod"])</value>
        </set-header>
        <set-header name="X-RateLimit-Amount" exists-action="override">
            <value>@((string)context.Variables["amountOfCalls"])</value>
        </set-header>
    </outbound>
    <on-error>
        <base />
    </on-error>
</policies>

simple-operation-without-fragment.policy.snippet

<policies>
    <inbound>
        <base />
        <rate-limit-by-key calls="@(int.Parse((string)context.Variables["amountOfCalls"]))" renewal-period="@(int.Parse((string)context.Variables["renewalPeriod"]))" counter-key="@(context.Subscription.Id)" remaining-calls-variable-name="remainingCallsPerSubscription" />
    </inbound>
    <backend>
        <base />
    </backend>
    <outbound>
        <base />
        <set-header name="X-RateLimit-Reset" exists-action="override">
            <value>@(((int)context.Variables["remainingCallsPerSubscription"]).ToString())</value>
        </set-header>
    </outbound>
    <on-error>
        <base />
    </on-error>
</policies>